Method for carbonizing carbonaceous materials



rJuly 22, 1958 M. F. NATHAN METHOD FOR CARBONIZING CARBONACEOUS MATERIALS I Filed May 16, 1956 mzoN www f ON INVENTOR.

MARVIN F. NATHAN AT ToRNEYs United States Patent O METHOD FOR CARBONIZING CARBONACEOUS MATERIALS Marvin F. Nathan, ,New York, N. .Y `assigner to The -M. W. Kellogg Company, Jersey City, N. I., a corporation of Delaware Application May 16, 1956, Serial No. 585,334

7 Claims. '(Cl'. 202-21) This invention relates to the treating of solid materials and more particularly to a method vfor the uidized treatment of carbonaceous .materials such as coal, shale, lignite, oil sands, etc., at lowtemperatures. Still more particularly, it relates to an improved method for recovering vsolids entrained in ilu'idizin'g .gases when carbonizing uidized carbonaceous materials at low temperatures.

This application is a -continua't'ion-in-.part .of my copenging application Serial No. 517,472, filed lune 23,

The treatment of carbonaceous solids to form valuable liquid, gaseous and solid products is well known in .the art. An example of one process -frequently employed entails .the treatment lof solids, such as coal at. elevated temperatures whereby volatile materials are-.released from the solids and a valuable solid residue is formed. It has been 'the practice inthe past to carry out .carbonization in both non-duid and iluid systems; however, -thepresent invention is concerned with a carbonization process Voi the fluid type wherein the various steps are .performed with a finely divided feed material which is maintained .in a highly turbulent state of agitation lby the passage therethrough of a iiui'dizing medium.

`In carrying out 'fluidized carbonization of carbonaceous materials, it has been found that several process steps .are necessary in order to provide a workable operation and assure a maximum yield of desirable vapor, liquid and solid products. More usually, the first step Vin the ,carbonization process concerns the proper preparation of the raw feed material. This involves not only proper Aselection and sizing of the carbonaceous solids to provide a readily fluidizible feed,- but also includes drying the solids to a minimum moisture content prior to further process- It has been found that certain finely divided carbonaceous materials, though easily iiuidized at low temperatures, when subjected `to more elevated temperatures suffer a change in physical characteristics and become soft and vgummy and the particles KVtend to agglomerate. For

example, many coals pass through va vso-called plastic state, usually at a temperature between about 700 F. and about 80.0 F. wherein the coal particles tend to stick together vand form large particles which resist uidization. Several methods of .combating this v.agglomerating tendency of coals and other Icarbonaceous materials have beensuggested, one of-.thermore successful of which cornprises subjecting the finely divided solid particles to a mild oxidation treatment prior to furtherhigh temperature processing. It has been Yfoundl that this method -of treatment alters the physical characteristics of the carbonaceous .material so as to minimize agglomeration of the solid particles. The changes which take place in the solids in a treatment of this type are not clearly understood; however, according to one theory the mild oxidation case hardens the particles -there'by substantially nullifying their 'sticking tendencies when they pass through the plastic state. When processing .carbonaceous materials, therefore, the :step .after `the drying operationmay 2,844,526 Patented July 22, 1.958

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involve pretreating the dry solidI particles `rat .an elevated temperature in the presence of a limited amount of voxygen. Dur-ing this process a portion ,of the vapor'izable compounds present. in the carbonaceous solids are ,released. The third and last step in the conventional solids carbonization process concerns the treatment -of .carbonaceous material ata still'higher temperature whereby the remaining vaporizable compounds are released therefrom and a carbonaceous product residue is produced. The vaporizable portionof the coal which 'is vcommonly known as tar comprises numerous organic compounds having a wide range of boilingpoi-nts. As `used ,-her'ein,

-the term tar includes any .volatile organic compounds released from the coal, either liquid or vapor and either cracked` or uncrac'ked. The composition of lthe .carbonaceous residue remaining after vaporization Aof the .tar depends on the type of carbonaceous ,feed material used', For example, when cai-.bonizingl coal'the ,residue material is commonly called chain Although the description and discussion of the invention will be directed primarily to coal carbonization, the term char will be used-hereinafter in a .broader sense to designate .any residue solids remaining after carbonization. il

In addition to the three proces ,ug `steps justtdescribed, a 'fourth operation may be necessary. ln carrying out'the drying step it is usually preferred to'heat the carbonaceous feed only to the minimum temperature necessary ,to .remove the surface water, which is, of course, the boiling point ofwater atv the pressure conditions vmaintained during this operation. The pretreating operation, .however, is carried out atan elevated4 temperature, .substantially above the temperature at which the' solids leave the drying zone. 'Only a portion of the heat requiredn this operation is supplied by 'the oxygen consumed therein. The remaining -heat required is furnished b y what may be called a -preheating step. It vis .possible .to provide the required preheat in conjunction with the dryingoperation or the pretreating operation, or it may be made an entirely separate and independent Vpart of the carbonization process. v Y

Each of the aforementioned processing steps, i. e., drying, preheating, pretreating and vcarbonization is custom.'- arily carried .out in a separate vessel, which necessitates the use of numerous transfer lines and standpipes .and involves an extensive solids recovery system when substantially Aall of the solids entering the system are tobe recovered.

It Ais an object of this invention to provide .an 'improved method and means for carrying out a solids carbonization process.

Another object of this invention is to provide irnproved method `and means for increasing product yield in the carbonization of carbonaceous materials.

` It is still another object of this inventionY to provide improved method and apparatus for recovering entrained solids inthe successive steps of 'uidized drying and preheating of carbonaceous materials.

Still' another object of this invention is to recover solids entrained in the drying ,of iluidized ,carbonaceous solids.

These and other objects ofthe invention will become more apparent'from the following detailed description and discussion.

In the method of this invention the aforementioned objects are achieved by `combining gases containing entrained carbonaceous solids fand gases containing. .entrained char ,particles and recovering thecoinbinedsolids as aproduct .by afscrubbing operation. .Speciiical-ly ,the carbonaceous solids are entrained-1in gases releasedafrom a vfluidized drying and Apreheatirig treatment :of carbonaceous solids and .the char particles lare entrained in aa gas obtained from a -prelimiua1;y,so1ids .recoyeryssystern 3 for the treatment of Ichar produced in the carbonization of carbonaceous solids. g

It is within the scope of this invention to treat various carbonaceous materials in the manner described, includ-l ing coals, shales, lignites, asphalts, oil sands, etc. The invention is particularly exemplified by its application to the treatment of coal, and further discussion of the invention is directed to the use of this material. It is not intended, however, that this particular application should limit the scope of the invention in any way.

Usually the rst step to be considered in a process for the carbonization of coal is concerned with surface water present in the coal feed which may, unless removed, prevent fluidization of the coal. One of the problems encountered when handling carbonaceous materials such as coal in a uidized system results from the tendency of the finely divided solids to agglomerate because of water condensed thereon. Most coals coming from a treating plant, for example, have a relatively high surface' or free water content, usually between about2 and about 15 percent by weight, or higher. Unless removed, this moisture causes the finely divided coal particles to stick together and resist uidization. Even after uidization is achieved, moisture may cause packing or bridging in process equipment of restricted cross section, such as, for example in feed hoppers, standpipes, etc. It is not always Aeconomically feasible to remove all the moisture from the coal; however, it has been found that agglomeration and packing of coal particles due to the presence of water is minimized if between about 50 percent and about 90 percent of the water initially present is removed. v

Several methods may be used for drying coal, such as direct contact with air or other gases at high temperatures, heating the coal by indirect heat exchange with a heated fluid, etc. In the latter method the heat transfer may be effected within a dense phase bed of the solids to be dried, or solids may be withdrawn from such a bed, passed through a heat exchanger and returned to the bed at an elevated temperature. Whichever method is used, a substantial quantity of gases result and these gases upon leaving the dense solids phase must be treated for the removal and recovery of entrained coal solids. Conventionally, gases from a fluid bed are passed through cyclones'. However, this provides only a partial recovery of solids and the gases from this treatment may contain from about 0.2 to about 100 grains per cubic foot of solids.

A similar problem of solids recovery may exist in other phases of the coal carbonization process. For example, if a preheating step is provided prior to carbonization, gases from this operation will also contain entrained coal solids. In the carbonization step itself and the pretreating operation, if one is provided, a different situation arises in that the gases contain large quantities of volatile compounds released from the coal. This presents a special problem which is not the concern of the invention herein disclosed.

The recovery of char after quenching, presents a similar problem to that encountered when drying the coal. Thus gases leaving the preliminary char recovery system will contain a quantity of residual solids.

In the method of this invention recovery of residual entrained coal solids and char particles is affected in a common water scrubbing system. The two gas streams may be introduced separately to the scrubbing system; however, more usually, it is preferred to combine the gases beforehand. In the'scrubbing step, the gases are contacted with a liquid such as water which is preferably introduced in such a manner as to provide countercurrent contact with the gases. The solids removed during this operation are present as a slurry and after removal from the scrubbing system will combine with the bulk of the char product. The amount of coal recovered in the scrubbing system is very small compared to the total 4 char product and usually amounts to less than about 0.8 percent thereof by weight. As a result, the properties and physical characteristics of the char are substantially unchanged by the coal present therein.

In a preferred embodiment of this invention coal is treated in a series of steps which involve drying, preheating, pretreating and low temperature carbonization. In carrying out the drying operation, raw coal suitably subdivided for fluidization, that is, of a size between about 10 mesh and about 5 microns is introduced into a first zone wherein it is commingled with dry heated coal in snicient quantity to elevate the entire mass of coal to a temperature suitable to effect the removal of water. The dry coal is then passed through a heater where it is further elevated in temperature by indirect heat exchange with a hot fluid and then into a second zone. The higher temperature coal in the second zone serves as the source of the coalcommingled with the wet` coal feed, and in addition, provides preheated coal for the next phase of the carbonization process. The entire drying and preheating step is conveniently conducted in a fluid system with both the low and high temperature zones containing a dense phase bed of fluidized coal superposed by a dilute phase of low solids concentration. Adequate turbulence to maintain each dense phase bed is provided by maintaining a linear gas velocity therein between about 0.5 and about 5 feet per second, or more usually between about 0.75 and about 3 feet per second. Under normal operating conditions the density of the beds thus provided various between about l0 and about 40 pounds per cubic foot. The temperatures in the two zones may vary, depending on the residence time of the coal in each zone and the moisture content of the raw coal feed. However, usually the rst zone is operated at a temperature between about 220 F. and about 325 F., and .the second zone is preferably maintained at a temperature of between about 350 F. and about 600 F. Fluidization of the solids in the low temperature zone is partially provided by moisture released from the coal and may be augmented by the introduction into this zone of air or an inert gas such as, for example ue gas, steam, etc. The coal in the high temperature or preheating zone is maintainied in a uid state by the introduction of a similar gasifying medium. It is necessary to circulate a sucient amount of coal from the low temperature zone through the heater to the high temperature zone and back to the low temperature zone to provide both the sensible heat acquired by the dry solids and the heat of vaporization of the water released therefrom. When operating in accordance with the zonal temperature ranges given, the amount of coal circulated relative to the raw coal feed rate is between about 2 and about 5 pounds per pound.

The heat transfer surface required for drying and preheating the coal is preferably provided by a conventional shell and tube heat exchanger with the solids being passed through the tubes in indirect heat exchange with a hot fluid passed through the exchanger shell. The heat required to dry the coal is provided by a fluid heating medium which may be a petroleum oil or vapor, or mixtures thereof, or other liquid or vapor material which is easily transported and can withstand relatively high temperatures. In general, liquid heating fluids are more satisfactory than gases because of their high specific heats and low volume relative to gases. Examples of suitable heating uids are residual petroleum oils, synthetic heat transfer liquids, inorganic salt mixtures, lead, mercury, etc.- The temperature at which the heating medium is employed varies with the temperature maintained in the drying zone and with the heat transfer characteristics of the heating medium. Usually, it is preferred to introduce the heating medium at a temperature between about 350 F. and about 1000o F. Temperatures greater than this are not desirable because ofthe danger of over heatingcoal particles `incontaet with the heat transfer surface.

The amount of heat exchange surface required to carry out the drying and preheating operations yvaries depending on several factors including the quantity of coal to be heated, the amount of moisture inthe coal, heat transfer coefficients, etc. More usually a surface area between about 0.02 and ,aboutl 0.30 ysquare foot per pound of fresh coal feed per hour is -sufcient ,to provide the desired drying and preheat.

The gases leaving the dense solids phase of the drying zone comprise Va mixture of steam and iluidizing gas and contain a quantity of entrained ldry coal solids. Removal of the major portion of'thesolids from this Agas is effected in a conventional lcyclone recovery system. However the gases leaving the dryer Vstill contain some solids, ymore usually between about 0.2 and about 100 grains per cubic feet of gas.

After leaving the preheating zone, the coal ispassed into `a pretreating zone wherein it is contacted with air or other oxygen containing gas and partially burned to provide the pretreating and case hardening effect previously discussed. The temperature at which this process step is carried out may vary over a range between about 600 F. and about 825 F.; however, rmore usually itl is'preferred to pretreat the coal in a more narrow range of temperature, that is between about 650 F. and about 800 F. As in the previous operations, the coal pretreatment is carried out in a conventional dense `phase lluidzed bed, wherein the coal is maintained in a turbulent fluid state by passage therethrough of a gasiform medium. Adequate turbulence to maintain the dense phase bed is provided by maintaining alinear gas velocity therein between about 0.5 and about 5 feet-per lsecond. Under normal operating conditions, fthe density-of the densephase bed thus provided Evaries vbetween about l'O and about `40 pounds per cubic'foot. Generally, a portion :or all of the fluidizing vmedium is suppliedin conjunction with the oxygen required'for pretreating. This maybe accomplished by diluting-'the oxygen with air, `vby using air alone or by diluting air or oxygen'with vsteam or other inert gas. The amount ofoxygen required `for pretreating is usually between about 0.02 andabout 0.08 pound per pound of `dry coal ffeed. 'To provide suficienttime for the pretreating combustion reactions-to take place, vthe rate of introduction of `coal to the pretreating l.zone is adjusted to allow an 'average 'particle residence time thereinof between about and "about 60 minutes.

vUpon entering the pretreating zone, dry `preheated'coal at a relatively low temperature-becomesiintimatelymixed with higher temperature pretreated coal vand -is/swiftly elevated to the temperature level prevailing in thisrzone. As the temperature of thedry coal-is increased-aportion of the lower boiling tar components-present inthe coal are vaporized and passed.into the lluidiz-ationvand combustion gases. Since oxygen isrelatively non-selec.- tivein its action, this phaseof the carbonization process may ,involve the consumption of Aaportion of vthe tar. Forthis reason, it is desirable tolimit the introduction ofoxygento the-pretreating-zone to the minimum amount necessary to prevent agglomeration -of the solids and maintain an-operable system. i

.Following pretreating, the coal'ispassed into a carbonization zone wherein-themajorjportion of the volatile components in the .coal 'are removed .and .a valuable residue `char is formed. This, the .major step ofthe process, as far as product yformation is concerned, `is also conveniently carriedout in a dense phase uidized bed similar to the drying, preheating and @pretreating beds previously described. Inorder tofeffect removal of the volatile vcoal components, a Alarge amount 'of heat must Ibe introduced to the carbonization zone. `Conventionallyfthisiheat may be supplied lfreine-.one .or more ofV :several sources, -for example-it may ibe provided in an inert .gas such as a fuel gas Aheated toa -hi'ghtemmadeup by the introduction into the carbonization zone of a ilue gas, steam or other 'extraneous inert gas.

The carbonization of .coal to remove `distillable tars therefrom Vand `produce a char residue product is conducted over a wide range of temperatures lusually f'between about 700 F. and about `2400 F. The preferred thermal range of operation is determined to a great extent bythe type of liquid lproduct desired; for example,

when it is preferred to distillthe coaltars with aninimum of cracking of volatile constituents, namely low temperature carbonizatiom thetemperature is `held to a minimum vof about 700 F. and Vnot more than about l000 -F. lThe type of coal is also of importance in establishing *the operating temperature since some coals are more difficult to distill than others. The carbonization zone contains a dense phase bed Vsuperposed by a disperse or dilute phase which may have a solids -concentration as low as 0.001 pound per cubic foot. Gases from the dense phase zone pass into the dilute phase which provides a preliminary `rough separation of vapors and solids. Further solids separation is provided 'by conventional means, such as, for example cyclones, filters, etc.

Substantially all of the desirable Vconstitu-ents of -coal are removed at the aforementioned carbonization'temperatures within a very short period of time,thatis between about 0.25 and about l0 minutes. As a further precaution to prevent agglomeration of the coal 'particles in the carbonizing zone, it is preferred to maintain a substantial ratio of char to fresh feed therein. This serves to dilute the fresh pretreated coal, which provides the desired beneficial effect; however, it also lmakes it necessary to substantially increa-sethe coal residence time. At the usual char to fresh'feed ratios maintained in the carbonization zone, that is between about 5 pounds per pound and about 50 pounds per pound, the particle residence time therein is between about 2 minutes and about 200 minutes, more usually between about 20 minutes land about. minutes.

'Carbonization may be carried outover'a'wide rangeof pressures; however, the pressure is Vusually maintained between `atmospheric and 500 p. s. i. g., preferablybetween about atmospheric and about'l00 p. s. i. g. fSincc 'a driving force is necessary for the passage of coal from the pretreating zone into'the carbonization zone the pretreating zone must operate at a pressure abovethe pressure in the carbonization zone; more usually the differential pres-sure betweenthe two -zones is between 'abouti/2 and about 2 p. s. i. By virtue-of its physical location above the pretreating zone, the drying zone may operate at a pressure either'higher or lower than the pressure'in the former zone. More usually, it is convenientfto maintain the pressure in the drying zone lower than thek pressure in the pretreating zone land as a result the drying zone is-ordinarily operated at between aboutl and-about 20 p. s. i. less than the pretreating zone.

l 'Hot char product from which the major portion of 'the Volatile constituents of the ,coal have been removedis withdrawn from the lower portion of the carbonizerand is passed through ak cooler wherein the temperature of the char is lowered by indirect heat exchange with a uid cooling medium. -When operating in accordance with the ranges of process variables previously enumerated the amount of this `material varies .between about 0.6 and` about"0.9gpound vperpound of v`wet feed coal. 'lhe remainder of the raw material delivered to the process is now 1n a vapor state, comprising a mixture of steam, combustion gases and tar vapors. The apparatus used 1n conjunction with the char cooling preferably comprises one or more conventional tubular heat' exchangers similar to those previously described in conjunction with drying and preheating the coal feed. The type and quantity of cooling fluid passed through the exchanger may be varied to meet the particular needs of the process. In general, uids similar to those previously disclosed for use in drying and preheating the coal are used. This operation is simplified and the cost is substantially reduced, if a common uid medium is used for both coal drying and preheating, and for cooling the product char. When operating with this type of system, a continuous circulating iluid Istream is provided, which extracts heat .from the hot char product and transfers it to the fresh coal feed., Inasmuch as the heat removed from the char in the cooling operation may not be suflicient to provide the heat required for drying and preheating the coal feed, `or vice versa, it is desirable when using a common 4heat exchange tluid to provide an additional heat source, such as for example a conventional tubular heater, or an additional source of cooling, such as for example a water cooler, Whichever is required.

IIn this preliminary cooling step, the char temperature is usually reduced to between about 700 F. and about 400 F., although it may be brought to `a still lower temperature if desired. The cooling tluid may be introduced to the cooler at any low temperature; however, when 'a common circulating stream is used the inlet temperature, of necessity, conforms to the temperature lof the fluid leaving the heaters which serve the drying and preheating stages of the carbonization process, i. e. between about 650 F. and about 350 F. The size of the cooler required varies with thea'mount and temperature of the char product, the heat transfer coeicients of the flowing streams and other operating variables; however, more usually a surface area between about 0.01 and about 0.10 square foot per pound of char product per hour is adequate to provide the desired cooling.

Normally, only a portion of the heat contained in the product char can be removed economically by indirect cooling, particularly when usin a common circulating heat exchange fluid. To further cool the char and provide a more easily handled product, Water is injected into the partially cooled lluidized char which is then passed into a receiver or char hopper. The quantity of water used for this purpose may vary; however, usually it is preferred to limit it to not more than the amount necessary to cool the char to the dew point of water at the pressure existing in the receiver, thus converting the entire quantity of cooling water to steam. By operating in this manner, advantage is taken of the high vaporization heat of `water to provide maximum cooling with a minimum of water consumption and at the same time provide additional vapors to maintain the char in the 'hopper in a uidized state. The cooled product is then convenientlyT removed from the hopper, delluidized by contact with additional water which condenses the iluidizing steam and is passed from the system by means of a conveyor or other suitable means.

The water used to cool the hot char may be introduced thereto prior to entry of this material into the char hopper, or after the char enters the hopper, or a portion may be admitted at both localities. It is preferred that the char be cooled to as low a temperature as possible; however, if a suitable use for higher temperature steam exists, the amount of cooling vwater may be controlled to provide a char temperature in the receiver substantially above the dew point of water. Also, although it is preferred to maintain the char in the hopper in a fluidized state, the defluidization of this material may be accomplished therein by increasing the vamount of cooling water introduced into the char to the point where liquid water is present in the hopper. The char is then 8 removed from this vessel as a slurry rather than as a fluidized mass.

The amount of water required to accomplish the second stage of the char cooling process varies with the initial temperatures of both thefchar product and the `water and the final temperature of the char. More usually the water is introduced at a low temperature, i. e. between about 60 F. and about 100 F. The pressure in the char hopper or receiver is also desirably maintained at a low level, usually less than the pressure inthe carbonizer, viz. between about 0 and about 5 p. s. i. g.

etting the pressure establishes the dew point temperature and accordingly the amount of water required as quench, which is usually between about 0.05 and about 0.15 pound per pound of char product.

The cool char which accumulates in the char hopper forms a dense fluidized solids bed above which there exists a conventional dilute phase zone of low solids concentration. The solids density in the dense phase bed is usually between about 15 and about 25 pounds per cubic foot; whereas, the concentration of `solids in the dilute phase is very small, often less than 0.1 pound per cubic foot. Vapors and solids leaving the hopper dilute phase pass through conventional separation means, for example cyclones, for the removal of a major portion of the solids. The char solids remaining in the gases, usually between yabout 0.2 and about grains per cubic foot of gas `are recovered in a secondary solids recovery system. `In order to minimize the facilities required for separating entrained solids, the overhead gases from the feed coal drier and preheater, which as previously noted contain entrained coal particles, are also introduced to the Isecondary solids recovery system.

In one embodiment, this system comprises a vertical elongated scrubbing tower, with bafes suitably dispersed therein to provide good liquid-vapor Contact. Within this tower, the combined vapors from the drier and preheater and char hopper are scrubbed with water to remove entrained coal and char particles. As in the preceding cooling step, the quantity and temperature of the scrubbing Water is controlled to maintain a suitable temperature within the scrubber so that a minimum amount of the steam introduced in the two vapor streams is condensed. Preferably the scrubbing liquid is supplied by recycling a warm solids-water slurry from the bottom of the scrubber and combining with this stream necessary makeup water from an outside source. Since the solidswater slurry is at the dew point temperature of the steam in the scrubber, usually between about 212 F. and about 240 F., this method of operation provides a relatively high temperature scrubbing stream and a minimum of steam is condensed in the process. In addition, by recycling, it is possible to closely control the scrubbing operation for maximum solids removal.

The recovered solids are removed from the scrubbing system as a slurry in `the scrubbing water. This slurry is conveniently mixed with char removed from the char hopper in order to lower its temperature and to reduce the dust problem associated with the finely divided solids product. As a result of this, the product char solids contain a mixture of coal and char; however, the amount of coal recovered in this operation is insigniiicant when compared to the char, being only between about 0.1 and about 0.8 percent thereof by weight, and when combined with the char is insucient in quantity to alter its properties or characteristics.

It is apparent that the aforedescribed method of solids recovery offers several important advantages. The combination treatment of gases from the char hopper and the drying and preheating zones substantially reduces the number of cyclones or other solids recovery equipment required. In addition, controlling the scrubbing operation to prevent condensation of the iluidizing steam provides an important heat economy and reduces the amount of scrubbing water` required forthe operation. Furthermore, introducing recovered coalinto the char prQdllCt not only provides aconvenientmethod ,of disposing of this material but also increases the Ychar' yield without affecting the properties of the char. 4

As previously mentioned, this Iinvention is notlmited inits scope to the treatment of coal, but encompasses the use of other carbonaceous feed materials, for example shales, asphalt, oilsands, etc. Similar processing considerations are important and similar operations are required when carbonizing these feed materials ,other than coal.` The conditions appropriate for each specific feed material are well known tothose skilledintthe ,art and for this reasondo not need repeating here.

As previously mentioned, the efuent vapors from the carbonizer comprise gaseous products of combustionvand various tar compounds plus a small amountof entrained char. The major portion of the `tar materials in the gases condense to liquids'at ordinary ,temperatures and form a .valuable product of the carbonization process.

To effect the separation of the normally liquid tar, they carbonizer gas stream is passed to a quenchtower where the vapors are contacted withazlow ltellperature liquid tar. This material not only provides the cooling `.eiect necessary to condense liquid tars but also effects the removal of entrained solids fromithe gases. The scrubbing and condensing liquid -is preferably obtained by Vcirculating tar condensed in thequenchtower through Aa cooler and recycling it to the upper portion ofthe tower. Within the tower are provided suitable baffles orplates whereby intimate contact betweenv ascending gases and downowing' liquid is effected. The pressure at which this Operation is carried out is controlled by the pressure in the carbonization zone, ,being somewhat lower, `usually between about and about 2 p. s. i. g. Ithas been found that the major portion of the desirable liquid tar compounds are condensed-bycooling the carbonizergasesto between about 150 F. and about 80 F. lTheremainirig vaporous tar compoundsand combustion products form a gas, which although lowin heat content, may be yused as a fuel. .If desired, of course, afurther separation between the uncondensed tar compounds and .combustion and fluidization gases may be effected.

In order kto more clearly describe ,the-invention and provide a better understanding thereof,.reference.is had to the accompanying drawing-which is a diagrammatic illustrationof process equipment used in carrying out a preferred yembodiment .of the invention, 1which .equipment comprises a unitary coal carbonizationsystern which includes a dryer, preheater, pretreater, carbonizer, char hopper, solids recovery systenntar l'quench tower and associated lines and heatexchange equipment.

Referring to the drawing, a.iinely subdivided coal at a temperature of about 60 F. .havinga particle size distribution between about 1`0-mesh and vabout 5 microns is delivered through conduit .2 into-feed standpipet wherein it is maintained in a dense'turbulentstate by passage therethrough of a tluidizing medium. `Enteringthe system the coal contains about 18% vvof surface water -by weight. From standpipe 4 the fluidized ycoalpasses downwardly throughl conduit 6 where 4it isfentrained in `additional gases, inthis instance steam, and-passed upwardly through a conduit :8 to a drier and preheater vessel V10 which is at a substantiallyhigher elevation. Within the drier vessel there is maintained-a dense ,highly turbulent bed .12 of dry coal particles .at atemperature of labout 270 F. The upper portion kofthisbed occupiesthe entire cross section of the drier vessel 1.0; however, in the lower 7portion thereof, the coal .is conned'within van annular Yspace lying between the walls vof the drier and a cylindrical elongated conduit-,extending upwardly through the bottom of the drier. Within .this'conduit lies al preheating zone 1.41in which there is' maintained ,a

higher temperature' dense bed of coal particles which overflow continuously into ,the lower temperature dry solids .b ed12. Above the ,densebelds ,of dry rand pliheated ,coal is Ya dilutephase16 of low solids concentration. Water vaporsreleased from the coal pass upwardly through this space into a cyclone 18ffromfwhich separated solids ,are returned to the I.dense Aphase of dry coalrand from which the vapors containing unseparated solids leave the drier 4through conduit 2.0.

To provide thev sensible heat required to heat the'wet coal vand the latent heat of vaporization of Athe water present therein, a stream of dry .coal is removed from the lannular dryingzone 12through `c onduit22, entrained in uidizing steam andupassed upwardly through conduit 2;6 and coal -heater 28 wherein the temperature ofthe coal is increased to about 480 F. From the heater the hot .coal is passed throughv the conduit 34 into conduit 14 .from which it eventually overflows to the .drying zone. in order to maintain the desired temperature `in the `drying -zone, it is necessary Ato overflow about .2 pounds ofsolids from ,conduit 14 per pound ofvwet vcoal introduced into the unit. Thus the solids circulation rate through the coal heater v28 is about 3 pounds Vof coal per pound of wet feed. The heat required in the combined v.drying and preheating operation is supplied at presentlby passing the circulating solids stream in indirect heat exchange with Va suitableheat-exchange medium.

It is preferredto employ as the ,heat exchange medium a cat crackerdecantedoil having an API gravity of about 1 '5` which .is heated by heatremoved from the system kin the manner described hereinafter. This material is introduced to heater 28 through conduitt) at atempera ture of rabout 680 F. andexits Atherefrom through conduit 32 at a temperature of about 400 F. The foregoing niethodof drying the coal issimple in application and in ,addition to eifectingremoval ofmoisture from the coal,`itprovides a ready means of adding to the coal the amount of preheat required ,before pretreating the coal, the next step in the process.

Although the hot coal leaving'heater 28 enters zone 14 in a fluidized condition, it may be desirable to` introduce additional gases, such asfor example steam through .conduit'13. Generally, the water vaporized in the drying zone is 'adequate to provide the desired turbulence inthe dry solidsbed; however, if necessary, an additional quantity of fiuidizing gases may also be 'introduced to zone 12. The amount of fiuidizinggases lpassed through each zone 'is controlled to provide a velocity therein of about 2feet per second, thereby maintaining a solids density in each bed of about 25 poundsrper cubic foot. As previously mentioned, the eiuent gases, from bot-h zones pass through a conventional cyclone .18 for the separation of entrained solids which are returned to zone 12. In spite of this, some solids, in quantity-equal to about 0;2 percent'by weight of the Awet feed are retained in the gases and leave the system through conduit 20.

The -combine'ddryingand preheating vessel 10 forms .a part of a single unitary vessel structure being superposed above a carbonization vessel 36 which contains within itslower portion a pretreating. zone 42. Passage of solids toprovide'some form 'of insulation to protect this .con-l duit. The rate of tiow `of solids from the preheating zone '114 to thepretreating zone 42 is controlled to maintaina more or less constant level invessel 10 vby a conventional plug valve 58 in -contact with .the bottom terminus ofthe Astandpipe-44. The pretreating zone 42,is separatedin part 'from the carbonization zone 40 by a vertical baflie 66 attached at the bottom and sides `to the inner wall kof the` carbonizer vessel 36. The vbottom por tion of the treating zone contains a distribution grid 60 for distributing fluidizing gases throughout the pretreated 1 1 coal. The pretreating zone opens upwardly into the carbonizing zone 40 and is separated therefrom by a grid 54 through which pretreated solids and vapors pass from the former to the latter zone.

The pretreating operation involves contacting the coal particles with' a controlled amount of oxygen, viz., about 0.04 pound per pound of preheated coal, whereby the coal particles are partially oxidized. In this manner, the physical characteristics of the particles are altered so as to nullify their tendency to adhere to each other as they are elevated in temperature and pass through the so-called plastic stage. The effectiveness of the pretreating step is dependent .not only on the extent to which the coal particles are oxidized, but is also a function of the pretreatment temperature, which is substantially increased over the preheating temperature, that is to about 725 F. The heat required to elevate the coal to this temperature is in normal operation supplied entirely from the heat of combustion of the coal. l'n carrying out the pretreating step, oxygen is introduced through conduit 64 and is distributed in the lower portion of the pretreating zone through grid 60. The oxygen may be supplied in a relatively pure state; however, more usually, it is preferred to use air, not only from the viewpoint of cost, but also to supply the additional gases necessary to maintain the solids in the pretreating zone in a uidized state. Although the-air admitted to the system normally suffices for this purpose additional gases such as, for example, steam, flue gas, etc., may be introduced through conduit 64 for fluidization purposes.

Coal entering the pretreating zone commingles with the solids contained therein and is partially oxidized and rapidly increased in temperature to that of the dense phase bed. In this process about 4 percent by weight of the preheated coal is reacted with the oxygen and converted to combustion products. The resulting mixture of pretreated coal and combustion gases, along with any portion of unconsumed oxygen, passes upwardly through the pretreating zone and through grid 54 into the carbonization zone 43. Within this zone there is maintained a dense phase turbulent bed of solid char particles at a substantially higher temperature, that is about 950 F. inasmuch as the pretreating zone is entirely beneath the top level of the solids in the carbonization zone, the grid 54 serves the dual purpose of `distributing the solids and gases leaving the pretreating zone and at the same time prevents passage of solids from the carbonization zone to the pretreating zone. By use of this separating means, it is possible to maintain two contiguous, yet distinct and separate dense phase beds of solids at quite different temperatures.

The preheated coal from zone 14 contains a large numbor of organic tar compounds varying widely in molecular structure and boiling point. The increase in temperature in this zone releases a portion of the lower boiling of these volatile compounds which pass upwardly into the carbonization zone 43 along with the pretreated solids and other gases. Upon entering the latter zone, the pretreated solids are quickly elevated to the temperature prevailing therein and large additional amounts of volatile components are released from the coal. The total time required in the two zones to carry out the process of tar removal is of short duration; however, in order to prevent solids from agglomerating and thereby assure an operable fluid process, it is desirable to maintain a large excess of pretreated solids in the pretreating zone and a similar excess of carbonized solids or char in the carbonization zone. This is effectively provided by sizing the pretreating and carbonization zones to allow an average particle residence therein of about minutes and about 60 minutes, respectively. The pretreated solids bed is maintained in a highly turbulent state by controlling the flow of vapors therethrough to provide a gas velocity of about 1.2 feet per second and a solids density of about 25 'pounds per cubic foot. Usually, this is effected by varying the oxygen'ratethrough conduit 64; however, if necessary,4 an extraneous gas (not shown) is admitted to zone 42. The degree'of turbulence and density of the solids in zone 43 is regulated in a similar manner.

The heat required for carbonizing the coal feed is also supplied by burning a portion of this material. For this purpose, about 0.03 pound of oxygen per pound of pretreated coal feed is introduced into the carbonization zone 43. In this operation also the oxygen is introduced in the form of air rather than in pure state, for the reasons previously given. Since one of the important features in optimizing liquid product yield is minimum contact between oxygen and volatile tar constituents, the oxygen required for carbonization is introduced into t-he bottom of the carbonization zone through conduit 70 which is at a point remote from the area of introduction of pretreated coal into the same zone. Oxidation and combustion of the carbonized coal particles proceeds rapidly and issubstantially completed before the carbonizer fluidizing and combustionl gases `reach the elevation at which the pretreated coal is present in quantity. The heat released by the combustion reactions is quickly transmited throughout the dense char bed providing a hot turbulent mass into which lower temperature pretreated solids are introduced. The. transfer of heat from the char particles to the pretreated solids in turn is equally swift and these solids reach the general char bed temperature level within a very short period of time. lThe process of devolatilization also proceeds at a fast rate and, by the time the pretreated solids reach the zone of combustion, they are substantially free of volatile tars.

By reason of the location of withdrawal conduit 62, char product from the main upper portion of the carbonization solids bed is forced to flow downwardly through the space provided between baffle 66 and the wall of the carbonizer vessel 36. Hot combustion and fluidizing gases ow upwardly through the samespace countercurrent to the descending char and provide a stripping action which assists in the removal of tar compounds from the char. The removal of volatile components from the coal in the carbonization zone, therefore, is effected in two ways, i. e., by elevating the pretreated coal particlesl to the carbonization temperature and by passing these particles downwardly `countercurrent to ascending combustion and uidizing gases before withdrawing them from the carbonization zone. While increased temperature is the major factor in eiecting tar removal, the stripping action of the combustion gases contributes to the total tar yield by removing some residual volatile materials.

The nal products of the carbonization process comprise a mixtureof tar vapors, steam and combustion gases, and carbonaceous char solids. Distribution of these products, Ybased on the Wet coal feed, is approximately 8 percent steam, 14 percent tar compounds and 76 percent char. The remainder of the coal is converted to combustion products to supply the process heat requirements. The gaseous products pass from the dense phase bed of char 43 upwardly into a dilute phase 4'7 and from thence through a cyclone separator 46 and conduit 52. Solids recovered in the cyclone are returned to the dense'char bed below the surface thereof. Char solids product are removed from the bottom of the `carbonizer 36 through conduit 62, are picked up by a stream of fluidizing steam and are passed through conduit 72 upwardly through a char cooler 74 for preliminarily cooling. The fluidized char solids enter the cooler at a temperature substantially the same as that maintained inthe carbonization zone, i. e., about 925 F., and exit from the cooler at a temperature of about 500 F. To extract the heat from the char, a cat cracker decanted oil of about 15 API gravity is introduced into the cooler 74 through conduit 73 at a temperature of about 400 F. This material ows through the cooler A74countt'ercurrent to the char and exists therefrom through'conduit 75, being heated in its passage through the cooler to about600." F. To provide a process ofy maximum thermal efficiency, a continuous circulating tluid system (not shown)v is used in which a common. hydrocarbon;fluidaccomplishes both char cooling andthe drying and preheating of the. coal' feed; Substantially. moreheat is required in the, drying and'preheating operation thanis obtainedby coolingthe char. Therefore,I in. order to thermally balance thesystem, it is necessary to supply an additional' amount of heat to the oil prior to: its introduction into the, coal heater 28'. This maybe done in any conventional'mannen such as, forexample, by passing the decanted' oil through a conventional redc heater (not shown) or other vconventional heating means.A The lower temperature char leaving cooler- 7,4 is passed, into a. char pot 78 from..` which it flows downwardly through conduit-80 into a char hopper 84 Where it accumulates in a conventional dense phase iluidized bed 88, super posed'byI a dilute phase 86. Although a substantial'amount of heat is removed'from the char inthe cooler 74, it is still muchtoo hotto be yielded as product. Itis preferable, for convenience in handlingthe char,that it be cooledto a much lower temperature and, if possible,.jby a more eicient method'than indirect heatvexchange.A The large amount of additional coolingrequired is,conveniently and. economically furnished by introducingwater into the. char through conduit 82 prior, to -passageo thechar into the. char hopper 84. T'hewater is immediately. converted toy steam,V thus providing, in addition. to the cooling effect, additionalv fluidizing medium suitable for maintaining the, solids in conduit S inra turbulentstate. The. amountof water combined with. the char is controlled.. to provide. a. temperature inrthe char. hopperat-or slightly above. the dew point ofwater atthepressure existing, therein.. In:V this specic illustration, thehopper. pressure is..about- 3.5. p. s. i.` g..and.thetemperatllreofthedensechar'bedSSis about 230 F. These conditions .are maintained by. cool. ing the char with about.0.0.7'pound.o'f. 80? F. waterper. poundf char, Operatingjn this manner'prevents .liquidwater frompassing into, the hopper,A andthe solids contained therein are. readily. maintained in a 'uidstate Steam which results from the charcoolingw disengages.

from the solidsin bed 88, passes-upwardlythroug'h dilute phase 86 and a conventional cycloneseparatori90v.forfthe removal .of entrained: solids,` and thence vthrough conduit 108gintofa secondary solids recovery. tower`98. .i Before entering thistower, the char hopper gases are. joined through.conduit.20,by the. gaseous-eiuentzfrom the drierand preheater 10. Withinthe solids recovery, tower 98i which contains a number, of. bales 106,. the combined` gasescontainingbothchar andcoal-solids are scrubbed with. water. introduced through. conduit` 100,` and spray;

ring. 1.0.4. Theresulting solids-,water slurry is withdrawn.- yfrom the,bottom ot'r the. recovery... tower through conduity 110, is dilutedwith additionalwatenfrom-conduit94 and; then.combined .with .char removed from the bottom ofthe char hopper. through conduit 92.y The slurry water serves',v

to condense any steamremaining in the char released,A

from the. hopper, therebydeuidizing-this materiahJ The;- totalsolids product. comprising .charadmixed with a smalle amount of coal is then removed from the unit'bya. con veyor or by other suitable means (not shown).

The temperature in the solids recovery tower is about 216 F., which, at'the'pressureeexisting therein, that is about 2 p. s..i. g., is equal to the dew p oint of water. It is preferred. in carrying out the solids recover-yn process thata minimum amount Yof the steam introducedrto tower 98 be condensed. In order to assure'this result, the temperature of the scrubbing water is maintained at subtantially the same level as the temperature within the tower. This is conveniently accomplished by heating the water prior to its introduction to the recovery tower, or more preferably by recycling hot slurry from conduit 110 to v sary to introduce extraneous warmy make-up Water through conduit 1'00to compensate for water in tlie' slurry combined with the char product; The scrubbed gases, consisting of essentially solids-free steam, accumulate in the. upper portion of ltower 98N and' are removedtherefrom through conduit 1022 rlhis gas, although low in pressure and temperature, contains a large amount of latent heat and'maybe used' in any-conventional` service where` low pressure steam is of value,

Tar vapors formed'injthepretreatingiand carbonization zones, together with the gaseous products of' combustion, pass from the:carbonizer:,Stithrough conduit' 52 and are introduced into a` tar quench tower'112`. A substantial portion of the tar-v inthese gases consistsofcompounds which are liquid' under normalI atmospheric conditions. These compounds are readily` condensed in theY quench tower by contacting' the hot gases witha` quantity of cool liquid tar. The liquid tar also serves asascrubbing medium andoperates -toremove charsolids entrained in the hot gases.- In-carryingout-'thisstep; the vapors are introducedintothebottomA ofthe tar quench tower and pass upwardly around-haines '11'4- countercnr-rent to liquid tar introduced into the-tower throughv conduit-'1421; `The cooler vaporssubsequently'- passthroughr anumber of perforated--trays-l-IG, througharnist extractor 1118- to remove-v entrainedliquid dropletsand exitf from Y the quench tower through conduit 120. The' liquids andsolids removed from thevaporsby-the scrubbing tar are transferred from' thel bottom oftheM quench' tower through pump 136'and arepassed-throughlconduitl 138i and cooler 140.I A portionofthe cooled material-is returned to the quench, tower through conduit'l'42 and theremainder is yieldedas-productthroughconduit 1438.L Ffthe temperature of the-gases-leavingthe-topoflthequenchY tower is about- 1609 F; This is stillsubstantially Aabove atmospheric temperatureand-inorder to lower the temperature of thegases still further theyare passed throughl akk Water cooler 122,` where-additional tarsare condensed; and then into-an accumulator 1-24 wherea further separation ofi gas and liquid takes place. This final cooling stepreduces the-temperatureU ofA the gasesto. about. 1.00? F. Ilhe gases -arereleased -from the-accumulator.- through'fconduit5126 -and Ypass-into `aCottrell.precipitator 128;. Liquid is-vremoved` fromtheprecipitator through. conduit. 132, is combined-with accumulator liquid from'` pump 130" and conduit..134,. and-this..combined stream: is .in turn. added toy the .tar product. passing. through: conduitr 138.` The finaly vapor product comprising primarily. .comhustion.

gases. and. steam. leaves. the.. precipitator. and the;- system throughconduit 130.

The.i preceding discussion has been directedtoral pre:

frred embodiment. of. theA lnvention, howeverl it' isu not intended that. the.,material presented. be construed ina any limiting sense,.hut.that.o.ther equipment, process:` conditions,.ows,etc.. are. also usedwithin the; scope. of the inventionz. For example, to limit the possibility',of-equipf fiorrrnothf.operatic'ms4 being providedin acommon scrub. bingsystem as described.

The `following data are presented'tor illustrate a typical commercial carbonization operation based on the processingrarrangement ofthedrwing..

Flows Lb./ hr.

Wet coall0 to 400 mesh 450,000

Water content; 35,000

Dry coal 415,000 Bases from drying zone- Water 61,500

Air 16,000

Coal 900 i Char product 345,000 Volatile product 60,000 Solids content I 1,000 Pretreater air 80,000 Carbonizer air 50,000 Char recycle (for pretreater temperature i control) 25,000 Feed coal heater- Coal circulation rate `l,250,000' Heating duid-15 API hydrocarbon oil 1,550,000l Product char coolercooling fluid-15 API hydrocarbon oil 1,550,000 Cooling water injected into char product n 28,000 Water to solids recovery tower 96,000' Tar quench tower reux 580,000 Temperatures: F. Wet coal Drying zone 270 Preheating zone 480 Pretreating zone 725 Carbonization zone V V 950 Char hopper 230 Solids recovery tower 216 Tar quench overhead Feed coal heateri Coal in 270 Coal out 480 Heating uid in 500 Heating fluid out 400 Product char coolerl 'Y v v Char in 9,50 Char out 500 Cooling uid in 400- Cooling fluid out 470 Cottrell precipitator ,150 Product char Tar product 350 Pressures: P. s. i. g.

' Drying zone 3.8` `Preheating zone 6.0 Pretreating zone (top) 11.0 Carbonization zone (disperse phase) 8.0 Char hopper 3.5 Solids recovery tower 2.0 Tar quench tower 6.0 Average residencey time of coal in: Minutes Pretreating zone 60v Carbonization zone 30 Gas velocity in: Ft./sec. Drying zone 2.0V Preheating zone 2.5 Pretreating zone 1.0 Carbonization zone 1.5 Density "of solids in: Lb./cu. ft. Drying zone 25 Preheating zone 25 Pretreating zone 22 Carbonization zone 18 toremove volatile constituents therefrom in which the solids arey heated in a drying zone in a dense phase fluidized bed to remove water therefrom, gases leaving said-dense phase bed are subjected to solids recovery treatment for removal of the major portion of the solids cntrained therein, the dry solids from said denseV phase lbed are passed into a carbonization zone wherein a char product is formed, the char product is removed from the carbonization zone, cooled and accumulated in a product zone, `the improvement which comprises passing the gases from lthe drying zone after solids recovery treatment to remove the major portion of the solids entrained therein a yscrubbing zone, contacting said substantially solids free gases while in the scrubbing zone with a liquid to form a solids-liquid slurry, removing the solids-liquid slurry from saidscrubbing zone and combining therewithV char products from said product zone.

2. The processdened in claim 1 in which the carbonaceous solids is coal.

3. The process defined in claim 1 in which the liquid which contacts the gases in the scrubbing zone is water.

4. In the process for treatment of carbonaceous solids to remove volatile constituents therefrom in which the solids are heated in a drying zone in a dense phase uidized bed to remove water therefrom, gases leaving said dense phase bed are subjected to a solids recovery treatment in which the major portion of the solids entrained therein are removed, the dry solids from said dense phase bed are passed into a carbonization zone wherein a char product is formed, the char product is removed fromV thercarbonization zone, cooled and accumulated in a product zone as a dense phase bed fluidized with steam, the improvement which comprises passing the gases from the drying zone after the major portion of the solids entrained therein have been removed to a scrubbing zone, passing gases from said product zone to said scrubbing zone, contacting said gases with a liquid while in the scrubbing zone toform a solids-liquid slurry,removing the solids-liquid slurry from said scrubbing zone and combining therewith char products from said product zone.

5. The process defined in claim 4 in which the carybonaceous solids is coal.

6. The process delinedin claim 4 in which the liquid whichcontacts the gases in the scrubbing zone is water.

7.` An apparatusfor treatmentof carbonaceous solids for the removal of volatile constituents, a Vessel adapted to define a drying zone, a vessel adapted to define a carbonizationzo'ne, a vessel adapted to define a char product zone, 'a vessel adapted to dene a scrubbing" zone, means'for conducting gases from saiddrying zone vessel to said scrubbing zone vessel, means for conducting solid product from said carbonization zone vessel to said product zone vessel, means for conducting gases from said product zone vessel to said scrubbing zone vessehmeans for supplying water to said scrubbing zone vessel, conduit means for removing char product from said char product zone vessel, means for introducing the solids-liquid slurry` from said scrubbing zone vessel to said conduit means.v

References Cited in the iile of this patentv FOREIGN PATENTS France Feb. 13, 1956 

1. IN THE PROCESS FOR TREATMENT OF CARBONACEOUS SOLIDS TO REMOVE VOLATILE CONSTITUENTS THEREFROM IN WHICH THE SOLIDS ARE HEATED IN A DRYING ZONE IN A DENSE PHASE FLUIDIZED BED TO REMOVE WATER THEREFROM, GASES LEAVING SAID DENSE PHASE BED ARE SUBJECTED TO SOLIDS RECOVERY TREATMENT FOR REMOVAL OF THE MAJOR PORTION OF THE SOLIDS ENTRAINED THREIN, THE DRY SOLIDS FROM SAID DENSE PHASE BED ARE PASSED INTO A CARBONIZATION ZONE WHEREIN A CHAR PRODUCT IS FORMED, THE CHAR PRODUCT IS REMOVED FROM THE CARBONIZATION ZONE, COOLED AND ACCUMULATED IN A PRODUCT ZONE, THE IMPROVEMENT WHICH COMPRISES PASSING THE GASES FROM THE DRYING ZONE AFTER SOLIDS RECOVERY TREATMENT TO REMOVE THE MAJOR PORTION OF THE SOLIDS ENTRAINED THEREIN A SCRUBBING ZONE, CONTACTING SAID SUBSTANTIALLY SOLIDS FREE GASES WHILE IN THE SCRUBBING ZONE WITH A LIQUID TO FORM A SOLIDS-LIQUID SLURRY, REMOVING THE SOLIDS-LIQUID SLURRY FROM SAID SCRUBBING ZONE AND COMBINING THEREWITH CHAR PRODUCTS FROM SAID PRODUCT ZONE. 